Atrial gland cells synthesize a family of peptides that can induce egg laying in Aplysia

Gregg Thomas Nagle, Sherry D. Painter, Katrina L. Kelner, James E. Blankenship

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

1. Endogenous peptides induced egg laying in the marine mollusc Aplysia in two ways: egg-laying hormone (ELH) from the neuroendocrine bag cells acts directly, causing the release of eggs from the ovotestis; peptides A and B from the atrial gland act indirectly, activating the bag cells to release ELH. Another atrial gland peptide (egg-releasing hormone; ERH) is a structural and functional hybrid of ELH and peptides A and B; it can act both directly and indirectly to induce egg laying. 2. Atrial glands were incubated in a mixture of3H-amino acids for 18 h, and the biosynthetically labelled peptides isolated using sequential Sephadex G-50 column chromatography and isoelectric focusing. Radiolabelled peaks were localized and bioassayed in intact animals. Bioactive peaks were then characterized functionally using two additional assays: egg laying in bag cell-less animals (ELH-like peptides) and in vitro induction of bag cell discharge (A- and B-like peptides). ERH-like molecules are active in both assays. Homogeneity of bioactive IEF peaks was assessed by SDS-PAGE. 3. Sephadex G-50 gel filtration of biosynthetically labelled atrial gland extracts reveals two major peptide peaks. Peak D (apparent M r 6,000) is strongly radiolabelled and contains most of the egg-laying activity, but has a low absorbance at 274 nm. Peak E (apparent M r 3,500) is weakly labelled and contains a small proportion of the total egg-laying activity, but has a large absorbance at 274 nm. 4. Isoelectric focusing of radiolabelled peptides in peak D reveals seven distinct ELH-like species (pI 5.5, 7.5, 8.5, 8.7, 8.9, 9.1, 9.4), and two peaks (pI 5.9, 8.1) that have both ELH-like and A-/B-like activity. The pI 8.1 peak may result from the comigration of peptide A with ERH or with an unidentified ELH-like peptide. It is not yet clear whether the pI 5.9 activity results from comigration of distinct peptides or from the presence of a previously uncharacterized ERH-like molecule. 5. Isoelectric focusing of radiolabelled peptides in peak E reveals five distinct ELH-like species (pI 7.3, 8.5, 8.7, 9.1, 9.4), and one peak (pI 8.9) with both ELH-like and A-/B-like activity. The pI 8.9 peak may result from the comigration of an ELH-like peptide with peptide B. Three of the ELH-like peptides (pI 8.5, 8.9, 9.1) found in peak E are probably identical to the ELH-like peptides found at the same pI's in peak D. 6. The ELH-like pI 7.5 species is a peptide complex held together by a disulfide linkage and hydrophobic interactions. The complex dissociates when treated with 2-mercaptoethanol and pyridine, resulting in a reduction in apparent molecular weight, and the appearance of one basic (pI 9.4) and two acidic (pI 3.3, 3.8) peptides. The pI 9.4 peptide presumably accounts for the ELH-like activity of the parent pI 7.5 complex but differs, based on its mobility on SDS-PAGE, from the pI 9.4 ELH-like peptide(s) described above. 7. These studies, utilizing a two-step purification procedure, functional bioassays, and SDS-PAGE to assess peptide homogeneity, indicate that atrial gland cells synthesize a surprisingly large number of peptides that can induce egg laying in Aplysia.

Original languageEnglish (US)
Pages (from-to)43-55
Number of pages13
JournalJournal of Comparative Physiology B
Volume156
Issue number1
DOIs
StatePublished - Nov 1 1985
Externally publishedYes

Fingerprint

Aplysia
peptide
Ovum
oviposition
peptides
egg
hormone
Peptides
Hormones
hormones
cells
Peptide Hormones
bags
Isoelectric Focusing
family
isoelectric focusing
Polyacrylamide Gel Electrophoresis
polyacrylamide gel electrophoresis
Assays
absorbance

ASJC Scopus subject areas

  • Physiology
  • Ecology, Evolution, Behavior and Systematics
  • Biochemistry
  • Animal Science and Zoology
  • Endocrinology

Cite this

Atrial gland cells synthesize a family of peptides that can induce egg laying in Aplysia. / Nagle, Gregg Thomas; Painter, Sherry D.; Kelner, Katrina L.; Blankenship, James E.

In: Journal of Comparative Physiology B, Vol. 156, No. 1, 01.11.1985, p. 43-55.

Research output: Contribution to journalArticle

Nagle, Gregg Thomas ; Painter, Sherry D. ; Kelner, Katrina L. ; Blankenship, James E. / Atrial gland cells synthesize a family of peptides that can induce egg laying in Aplysia. In: Journal of Comparative Physiology B. 1985 ; Vol. 156, No. 1. pp. 43-55.
@article{b9d7ab29c57f4280a0f7a6b69872884c,
title = "Atrial gland cells synthesize a family of peptides that can induce egg laying in Aplysia",
abstract = "1. Endogenous peptides induced egg laying in the marine mollusc Aplysia in two ways: egg-laying hormone (ELH) from the neuroendocrine bag cells acts directly, causing the release of eggs from the ovotestis; peptides A and B from the atrial gland act indirectly, activating the bag cells to release ELH. Another atrial gland peptide (egg-releasing hormone; ERH) is a structural and functional hybrid of ELH and peptides A and B; it can act both directly and indirectly to induce egg laying. 2. Atrial glands were incubated in a mixture of3H-amino acids for 18 h, and the biosynthetically labelled peptides isolated using sequential Sephadex G-50 column chromatography and isoelectric focusing. Radiolabelled peaks were localized and bioassayed in intact animals. Bioactive peaks were then characterized functionally using two additional assays: egg laying in bag cell-less animals (ELH-like peptides) and in vitro induction of bag cell discharge (A- and B-like peptides). ERH-like molecules are active in both assays. Homogeneity of bioactive IEF peaks was assessed by SDS-PAGE. 3. Sephadex G-50 gel filtration of biosynthetically labelled atrial gland extracts reveals two major peptide peaks. Peak D (apparent M r 6,000) is strongly radiolabelled and contains most of the egg-laying activity, but has a low absorbance at 274 nm. Peak E (apparent M r 3,500) is weakly labelled and contains a small proportion of the total egg-laying activity, but has a large absorbance at 274 nm. 4. Isoelectric focusing of radiolabelled peptides in peak D reveals seven distinct ELH-like species (pI 5.5, 7.5, 8.5, 8.7, 8.9, 9.1, 9.4), and two peaks (pI 5.9, 8.1) that have both ELH-like and A-/B-like activity. The pI 8.1 peak may result from the comigration of peptide A with ERH or with an unidentified ELH-like peptide. It is not yet clear whether the pI 5.9 activity results from comigration of distinct peptides or from the presence of a previously uncharacterized ERH-like molecule. 5. Isoelectric focusing of radiolabelled peptides in peak E reveals five distinct ELH-like species (pI 7.3, 8.5, 8.7, 9.1, 9.4), and one peak (pI 8.9) with both ELH-like and A-/B-like activity. The pI 8.9 peak may result from the comigration of an ELH-like peptide with peptide B. Three of the ELH-like peptides (pI 8.5, 8.9, 9.1) found in peak E are probably identical to the ELH-like peptides found at the same pI's in peak D. 6. The ELH-like pI 7.5 species is a peptide complex held together by a disulfide linkage and hydrophobic interactions. The complex dissociates when treated with 2-mercaptoethanol and pyridine, resulting in a reduction in apparent molecular weight, and the appearance of one basic (pI 9.4) and two acidic (pI 3.3, 3.8) peptides. The pI 9.4 peptide presumably accounts for the ELH-like activity of the parent pI 7.5 complex but differs, based on its mobility on SDS-PAGE, from the pI 9.4 ELH-like peptide(s) described above. 7. These studies, utilizing a two-step purification procedure, functional bioassays, and SDS-PAGE to assess peptide homogeneity, indicate that atrial gland cells synthesize a surprisingly large number of peptides that can induce egg laying in Aplysia.",
author = "Nagle, {Gregg Thomas} and Painter, {Sherry D.} and Kelner, {Katrina L.} and Blankenship, {James E.}",
year = "1985",
month = "11",
day = "1",
doi = "10.1007/BF00692925",
language = "English (US)",
volume = "156",
pages = "43--55",
journal = "Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology",
issn = "0174-1578",
publisher = "Springer Verlag",
number = "1",

}

TY - JOUR

T1 - Atrial gland cells synthesize a family of peptides that can induce egg laying in Aplysia

AU - Nagle, Gregg Thomas

AU - Painter, Sherry D.

AU - Kelner, Katrina L.

AU - Blankenship, James E.

PY - 1985/11/1

Y1 - 1985/11/1

N2 - 1. Endogenous peptides induced egg laying in the marine mollusc Aplysia in two ways: egg-laying hormone (ELH) from the neuroendocrine bag cells acts directly, causing the release of eggs from the ovotestis; peptides A and B from the atrial gland act indirectly, activating the bag cells to release ELH. Another atrial gland peptide (egg-releasing hormone; ERH) is a structural and functional hybrid of ELH and peptides A and B; it can act both directly and indirectly to induce egg laying. 2. Atrial glands were incubated in a mixture of3H-amino acids for 18 h, and the biosynthetically labelled peptides isolated using sequential Sephadex G-50 column chromatography and isoelectric focusing. Radiolabelled peaks were localized and bioassayed in intact animals. Bioactive peaks were then characterized functionally using two additional assays: egg laying in bag cell-less animals (ELH-like peptides) and in vitro induction of bag cell discharge (A- and B-like peptides). ERH-like molecules are active in both assays. Homogeneity of bioactive IEF peaks was assessed by SDS-PAGE. 3. Sephadex G-50 gel filtration of biosynthetically labelled atrial gland extracts reveals two major peptide peaks. Peak D (apparent M r 6,000) is strongly radiolabelled and contains most of the egg-laying activity, but has a low absorbance at 274 nm. Peak E (apparent M r 3,500) is weakly labelled and contains a small proportion of the total egg-laying activity, but has a large absorbance at 274 nm. 4. Isoelectric focusing of radiolabelled peptides in peak D reveals seven distinct ELH-like species (pI 5.5, 7.5, 8.5, 8.7, 8.9, 9.1, 9.4), and two peaks (pI 5.9, 8.1) that have both ELH-like and A-/B-like activity. The pI 8.1 peak may result from the comigration of peptide A with ERH or with an unidentified ELH-like peptide. It is not yet clear whether the pI 5.9 activity results from comigration of distinct peptides or from the presence of a previously uncharacterized ERH-like molecule. 5. Isoelectric focusing of radiolabelled peptides in peak E reveals five distinct ELH-like species (pI 7.3, 8.5, 8.7, 9.1, 9.4), and one peak (pI 8.9) with both ELH-like and A-/B-like activity. The pI 8.9 peak may result from the comigration of an ELH-like peptide with peptide B. Three of the ELH-like peptides (pI 8.5, 8.9, 9.1) found in peak E are probably identical to the ELH-like peptides found at the same pI's in peak D. 6. The ELH-like pI 7.5 species is a peptide complex held together by a disulfide linkage and hydrophobic interactions. The complex dissociates when treated with 2-mercaptoethanol and pyridine, resulting in a reduction in apparent molecular weight, and the appearance of one basic (pI 9.4) and two acidic (pI 3.3, 3.8) peptides. The pI 9.4 peptide presumably accounts for the ELH-like activity of the parent pI 7.5 complex but differs, based on its mobility on SDS-PAGE, from the pI 9.4 ELH-like peptide(s) described above. 7. These studies, utilizing a two-step purification procedure, functional bioassays, and SDS-PAGE to assess peptide homogeneity, indicate that atrial gland cells synthesize a surprisingly large number of peptides that can induce egg laying in Aplysia.

AB - 1. Endogenous peptides induced egg laying in the marine mollusc Aplysia in two ways: egg-laying hormone (ELH) from the neuroendocrine bag cells acts directly, causing the release of eggs from the ovotestis; peptides A and B from the atrial gland act indirectly, activating the bag cells to release ELH. Another atrial gland peptide (egg-releasing hormone; ERH) is a structural and functional hybrid of ELH and peptides A and B; it can act both directly and indirectly to induce egg laying. 2. Atrial glands were incubated in a mixture of3H-amino acids for 18 h, and the biosynthetically labelled peptides isolated using sequential Sephadex G-50 column chromatography and isoelectric focusing. Radiolabelled peaks were localized and bioassayed in intact animals. Bioactive peaks were then characterized functionally using two additional assays: egg laying in bag cell-less animals (ELH-like peptides) and in vitro induction of bag cell discharge (A- and B-like peptides). ERH-like molecules are active in both assays. Homogeneity of bioactive IEF peaks was assessed by SDS-PAGE. 3. Sephadex G-50 gel filtration of biosynthetically labelled atrial gland extracts reveals two major peptide peaks. Peak D (apparent M r 6,000) is strongly radiolabelled and contains most of the egg-laying activity, but has a low absorbance at 274 nm. Peak E (apparent M r 3,500) is weakly labelled and contains a small proportion of the total egg-laying activity, but has a large absorbance at 274 nm. 4. Isoelectric focusing of radiolabelled peptides in peak D reveals seven distinct ELH-like species (pI 5.5, 7.5, 8.5, 8.7, 8.9, 9.1, 9.4), and two peaks (pI 5.9, 8.1) that have both ELH-like and A-/B-like activity. The pI 8.1 peak may result from the comigration of peptide A with ERH or with an unidentified ELH-like peptide. It is not yet clear whether the pI 5.9 activity results from comigration of distinct peptides or from the presence of a previously uncharacterized ERH-like molecule. 5. Isoelectric focusing of radiolabelled peptides in peak E reveals five distinct ELH-like species (pI 7.3, 8.5, 8.7, 9.1, 9.4), and one peak (pI 8.9) with both ELH-like and A-/B-like activity. The pI 8.9 peak may result from the comigration of an ELH-like peptide with peptide B. Three of the ELH-like peptides (pI 8.5, 8.9, 9.1) found in peak E are probably identical to the ELH-like peptides found at the same pI's in peak D. 6. The ELH-like pI 7.5 species is a peptide complex held together by a disulfide linkage and hydrophobic interactions. The complex dissociates when treated with 2-mercaptoethanol and pyridine, resulting in a reduction in apparent molecular weight, and the appearance of one basic (pI 9.4) and two acidic (pI 3.3, 3.8) peptides. The pI 9.4 peptide presumably accounts for the ELH-like activity of the parent pI 7.5 complex but differs, based on its mobility on SDS-PAGE, from the pI 9.4 ELH-like peptide(s) described above. 7. These studies, utilizing a two-step purification procedure, functional bioassays, and SDS-PAGE to assess peptide homogeneity, indicate that atrial gland cells synthesize a surprisingly large number of peptides that can induce egg laying in Aplysia.

UR - http://www.scopus.com/inward/record.url?scp=0022193674&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0022193674&partnerID=8YFLogxK

U2 - 10.1007/BF00692925

DO - 10.1007/BF00692925

M3 - Article

C2 - 3836231

AN - SCOPUS:0022193674

VL - 156

SP - 43

EP - 55

JO - Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology

JF - Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology

SN - 0174-1578

IS - 1

ER -